The present invention relates to an automatic pocket opening sewing machine having a cutting device for notching cuts into the pocket.
A device for forming notching cuts at the ends of pocket openings in sewn material parts is known from Federal Republic of Germany Pat. No. 23 22 696. It includes two wedge shaped knives, each of which is movable to make a respective notching cut in the material. The wedge knife which is located closest to the place of sewing, i.e. to the sewing needles, is in drive connection with a lever transmission which moves that displaceable knife over the same distance as the advance of the sewn material, while the other wedge knife is stationary. The sewn material parts which are to be brought into the cutting position must move over a relatively large path in order that the starting point of the pocket opening seam then coincide with the stationary wedge knife which is arranged furthest away from the place of sewing. This known device has the disadvantage that the path to be moved over until the cutting position of the sewn material parts is reached is large enough that it increases the unproductive machine time. As a result, rational and hence profitable production of small size pocket openings cannot be achieved because the sewn material parts must travel over too long a path before arriving at the cutting position, where the notching cuts are made. Travel of those parts over a shorter distance would be preferred.